Author Topic: 300 AAC & Cast Lead Boolit question (Read 1913 times)

bikerbeans · « **on:** January 03, 2013, 12:49:07 PM »

Hi All,
Anybody out there shooting 200+ grain cast lead boolits at subsonic velocity from their AR platform, 300 AAC Blkout? Just looking to hear from folks who have actually tried cast lead boolits in the 300 AAC AR.
thanks
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SharonAnne · « **Reply #1 on:** January 03, 2013, 02:29:44 PM »

sorry, I cannot help you. Just wanted you to know you were not being ignored.

bikerbeans · « **Reply #2 on:** January 04, 2013, 12:34:53 AM »

Quote from: SharonAnne on January 03, 2013, 02:29:44 PM

sorry, I cannot help you. Just wanted you to know you were not being ignored.

SharonAnne,

Thank you. Maybe I should have asked how hard is it to remove lead from the gas block on an AR?

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SharonAnne · « **Reply #3 on:** January 04, 2013, 03:04:17 PM »

propane torch? maybe easier to replace it.

WayneS · « **Reply #4 on:** January 05, 2013, 01:52:32 PM »

For info strictly on AR and cast I suggest you go to the CAST BOOLITS forum, There are several there that use cast in their .223's, 300 ACC's and AR-10's. If you have a 1-8 twist I have a 242 gn 5 cavity mold for sale. You will hear this bullet referred to as the 311- 247

Dezynco · « **Reply #5 on:** January 08, 2013, 03:32:59 PM »

I just noticed your question. I run 200gr cast lead through my 300 whisper all the time. I run them both supersonic and subsonic (only 1300-1500 fps). Never had any trouble. As a matter of fact, I ran 300 rounds without cleaning - just to prove a point to a few of my buddies. It was pretty filthy! I slid the gas block off and cleaned it good. Used a pipe cleaner to clean out the tube. The worst is cleaning the grime off the bolt and carrier. The bullet I use a lot is the RCBS 200 grainer with a gas check

bikerbeans · « **Reply #6 on:** January 08, 2013, 05:17:26 PM »

Thanks for the input. We have a couple of molds on the way and hope to be casting and plinking shortly. Going to try these in single shot 300 AAC before putting them in the autoloader, just to make sure we don't have a leading issue.

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Dezynco · « **Reply #7 on:** January 09, 2013, 12:06:10 AM »

No problem. Just remember that you don't want to make your bullets too hard. Of course you don't want them too soft either. I use wheel weight lead with no problems. Bullets that are too hard are worse about leading the barrel because the bullet doesn't grip the rifling as well as it should, which allows it to slip across the rifling in the barrel, thus causing lead fouling to develop.

You shouldn't have any problem with lead fouling in the gas block, BTW. If will just get grimy from the bullet lube that burns off in the barrel. If ther's lead fouling, it will be in the barrel. However, I've never had any problems.

Don't use bullet lube that is too hard, and don't jack up the velocities. You really can't run very high velocities in the Blackout anyway, the case is too small.

Reloader 7 works well with cast bullets, as does AA1680 (for subsonic loads around 800 - 1000 fps)

WayneS · « **Reply #8 on:** January 10, 2013, 04:31:30 AM »

THE best source for asking questions about casting and shooting cast bullet is the CAST BOOLIT
forum.Just remember, one answer to a question is just an openion, three or more answers that say about the same thing should be considered good info.

454Puma · « **Reply #9 on:** January 19, 2013, 06:02:59 PM »

Yep alot of folks do. I don't have a 200gr plus mold in .30 But I shoot the Lee 170 gr. GC over 12gr IMR 4227 -not a sub but runs at 1385 fps -very accurate plinker in my 300 blk.

PS shooting lead in the AR platform is perfectly fine - no leading if you use a good lube- I've been using Lee Alox with zero leading running at 2000 + fps! I run cast also in my 5.56mm at over 2300 fps. And no it does not clog up the gas tube!

bikerbeans · « **Reply #10 on:** March 12, 2013, 07:05:52 AM »

Update, sorta! $:-\$

I now have a 16.1" 300 aac upper with 1:8 twist and a couple of different lowers, spike's tact & a polymer New Frontier (it was cheap and I thought I would see if it would work). after 49 rds down range with 230 & 247 g cast boolits I am 100% sure I need a reduced power buffer spring. Gun shoots and ejects the MT just fine but doesn't quite make a full stroke so will not pickup the next round. If I launch 147 g FMJBTs @ 1800 fps the gun cycles fine with both lowers. Per load data I am at the upper limit of subsonic so increasing powder charge to get the gun to cycle isn't an option. I just ordered two RP buffer springs from Wolff (18 business day backlog

) and will report back after installation and retesting. I thought about trimming the existing springs but decided against it, for now.

Without a can the 300 is fairly quite. I was shooting in my test cell (inside my pole barn) which is about 100' from my house and my wife did not hear the gun go off. Will be big fun with a can, especially if it actually functions as a semiauto carbine.

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Dezynco · « **Reply #11 on:** March 13, 2013, 02:13:50 AM »

bikerbeans,
Before you give up, give the bolt and bolt carrier a thorough cleaning. Then reassemble them and use a good lubricant like Lucas Gun Oil. Use the oil on the exterior of the bolt carrier also. AR's don't like to run dry, just don't get oil in the chamber.

You might consider a Nickle Boron bolt also. I know they're a little pricey but they really work well. I purchased a complete nickle boron bolt carrier group for mine and it really slicked things up. I was able to reduce my powder charge by a whole grain just because the nickle boron is so much slicker.

bikerbeans · « **Reply #12 on:** March 14, 2013, 08:49:58 AM »

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I had throughly cleaned & lubed the bolt carrier/upper before my range trip Monday. I repeated the cleaning yesterday and then start experimenting by removing a 1/2 of a coil at a time from the buffer spring (I was to impatient to wait 18 business days for the RP buffer spring from Wolff). Turns out with my setup the magic number is 5 coils. After cutting 5 coils off the buffer spring the gun now cycles 100% of the time with a 230 grain lee cast boolit and 9.9 grains of H110, WSR primer, 2.255" OAL, max. lee FC.
Now it's time for accuracy and velocity testing. My first test will be with air cooled WW lead boolits. Then will repeat with water quenched WW lead.

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rdmallory · « **Reply #13 on:** March 14, 2013, 02:39:08 PM »

I would rather pay a little more and run Berry's plated.

Doug

bikerbeans · « **Reply #14 on:** March 15, 2013, 12:42:04 AM »

Quote from: rdmallory on March 14, 2013, 02:39:08 PM

I would rather pay a little more and run Berry's plated.

Doug

Doug,

I prefer to pay $0.00. I have a free source of WW lead, the mold and a pot.

My wife and son have itchy trigger fingers so I would go broke buying bullets, especially with today's market insanity.

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Dezynco · « **Reply #15 on:** March 15, 2013, 02:07:43 AM »

start experimenting by removing a 1/2 of a coil at a time from the buffer spring

Quote

[/size]

[/size]Yea, I did that with mine, I cut 1/2 too many coils and the spring didn't have enough "OOMPH" left to close the bolt. Had to replace the recoil spring. Just remember if you go back to full power loads, you'll probably want to get you a replacement spring.

bikerbeans · « **Reply #16 on:** March 15, 2013, 02:43:38 AM »

Quote from: Dezynco on March 15, 2013, 02:07:43 AM

start experimenting by removing a 1/2 of a coil at a time from the buffer spring
Quote

Yea, I did that with mine, I cut 1/2 too many coils and the spring didn't have enough "OOMPH" left to close the bolt. Had to replace the recoil spring. Just remember if you go back to full power loads, you'll probably want to get you a replacement spring.

I was worried about now having enough spring left to close the bolt. Taking a 100 rds to the range today for further testing. I am going to leave this gun a dedicated subsonic heavy cast bullet shooter so I shouldn't have to worry about a spare full power spring. My guess is having reduced the spring will mean the gun will be more sensitive to malfunction as it gets dirty. Up side is it will mean I have be forced into keeping the action clean. I guess this problem could have been solved with a lighter weight BCG but they are big money now and I ain't brave enough to remove weight from on myself.

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bikerbeans · « **Reply #17 on:** March 18, 2013, 03:59:56 PM »

Friday after 55 rounds I started having feeding problems. Oil completely gone from the bolt. I used Rem Oil because I couldn't find my white lithium grease that always works in my wife's M4. Completely cleaned and re-lubed with the correct (in my mind) grease and will head back to the range in a day or so.

I did some more research and found that Accurate/Ramshot/Western says their 4100/Enforcer powder will not cycle a 300 aac autoloader with bullets heavier than 155g. I am using H110 which is very close to the same burn rate.

Went to a gun shop today and came out with 2 pounds of 5744 for a pre-panic price. Accurate also says their 5744 and 1680 powders will only cycle a semi-auto with subsonic bullets of at least 210 g. I have already downloaded Accurate's data for 5744 in the 300 BO so if the H110 doesn't pan out I now have a backup plan. Now to cast a thousand or so 230 grain Lee boattails and let the fun begin.

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454Puma · « **Reply #18 on:** March 18, 2013, 04:47:01 PM »

Don't go cutting your springs! If anything change your buffer- but don't cut the spring! Powders used for the 300 Blk have to be preety slow burners. To fast and you get to much pressure, to slow then you can't get enough in the case to cycle the action.

This is where your powder needs to be to function in the AR platform ! 60-71- disregaurd/do not use 133-143!

IMR, Co IMR 7828
60	VihtaVuori N110	133	Alliant Reloder 25
61	Hodgdon LIL'GUN	134	VihtaVuori N170
62	Hodgdon H110	135	Accurate Arms Magpro
63	Winchester 296	136	Hodgdon H1000
64	IMR, Co IMR 4227	137	Ramshot Magnum
65	Hodgdon H4227	138	Hodgdon RETUMBO
66	IMR, Co SR 4759	139	VihtaVuori N570
67	Accurate Arms 5744	140	Accurate Arms 8700
68	Accurate Arms 1680	141	Hodgdon H870
69	NORMA 200	142	VihtaVuori 24N41
70	Alliant Reloder 7	143	Hodgdon H50BMG
71	IMR, Co IMR 4198

bikerbeans · « **Reply #19 on:** March 19, 2013, 12:57:12 AM »

454,

H110 will not cycle my 300aac at subsonic velocity with either a 230 or 247g bullet. With a completely clean and well lubed upper it still wouldn't cycle. I did the spring modification because I only had H110 to work with and the spring is cheapest part in case I screw it up.

I now have 5744 and I have a second lower with a stock spring. If 5744 will work at subsonic velocity with a stock buffer spring the I will save the H110 for other loadings and put the modified buffer spring in the "lessons learned" container.

Thanks for you input.
'
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454Puma · « **Reply #20 on:** April 02, 2013, 06:40:23 PM »

Bikerbeans
So your saying the 9.5 gr load of H110 wouldn't cycle your gun? What gas length do you have? Pistol or Carbine? If it's pistol I'd say your port dia is way off! As in to small. Now under stand -you have to use 9.5 gr or more- not less!
Here is Hodgdon data:

220 GR. SIE HPBT

IMR

IMR 4198

.308"

2.260"

11.5

1036

25,300 CUP

220 GR. SIE HPBT

Hodgdon

H4198

.308"

2.260"

11.5

1068

25,600 CUP

220 GR. SIE HPBT

IMR

IMR 4227

.308"

2.260"

10.5

1014

28,800 CUP

220 GR. SIE HPBT

Winchester

296

.308"

2.260"

9.9

1050

29,700 CUP

220 GR. SIE HPBT

Hodgdon

H110

.308"

2.260"

9.9

1050

29,700 CUP

220 GR. SIE HPBT

Hodgdon

Lil'Gun

.308"

2.260"

9.0

1077

31,100 CUP

230 GR. BER TACT

IMR

IMR 4227

.308"

2.260"

10.2

1065

37,100 CUP

230 GR. BER TACT

Winchester

296

.308"

2.260"

9.5

1085

34,500 CUP

230 GR. BER TACT

Hodgdon

H110

.308"

2.260"

9.5

1085

34,500 CUP

230 GR. BER TACT

Hodgdon

Lil'Gun

.308"

2.260"

8.7

1077

28,900 CUP

bikerbeans · « **Reply #21 on:** April 03, 2013, 05:35:12 AM »

454,

The barrel is a 16" carbine 300 AAC and the lower has the standard civilian buffer system. I loaded 9.9 grains of H110 with a the lee boolit (as cast at 225 grains) and it is a no go with the standard buffer spring. I have 3 carbine lowers and none will cycle correctly with the load. I removed 5 turns from one buffer spring and now the gun cycles everytime.

I am thinking if I use the slower burning powders the gun might function with a standard spring, but right now I am rich in H110 so I am going to stick with the reduced spring.

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454Puma · « **Reply #22 on:** April 03, 2013, 06:46:38 PM »

bikerbeans
So what COAL were you seating those bullets too? Sometimes seating them shorter will get you the pressure you need to cycle. Seeing it's an 300 AAC upper you'd think they had the right port size, had you contacted AAC about it maybe they can fix it cause as I said you should never have to cut your spring to get it to cycle! Not cycling Subs is almost always the port is to small. I'm a member on the 300 Blk out forum I'll post the question on the AAC forum and see what they say.

bikerbeans · « **Reply #23 on:** April 04, 2013, 03:35:21 AM »

Quote from: 454Puma on April 03, 2013, 06:46:38 PM

bikerbeans
So what COAL were you seating those bullets too? Sometimes seating them shorter will get you the pressure you need to cycle. Seeing it's an 300 AAC upper you'd think they had the right port size, had you contacted AAC about it maybe they can fix it cause as I said you should never have to cut your spring to get it to cycle! Not cycling Subs is almost always the port is to small. I'm a member on the 300 Blk out forum I'll post the question on the AAC forum and see what they say.

454
COAL is 2.255". I am going to the range tomorrow with my chrony and see what velocity I am getting. If I can speed up the boolit a tad and stay subsonic that might help.
All the published pressures for the 300 BO subsonic loads are all fairly low compared to the lighter bullets. Accurate powder states in their load data for the BO that cycling of an autoloader with the subsonic rounds is marginal. Accurate's data for the subsonic rounds use powders that are slower than H110, therefore more pressure when the bullet passes the gas port. I am thinking my main problem is using too fast a powder. If I can scrounge up a can of I or H 4198 I will test my theory.
Thank you for you help and input. Also, I have a second test platform once the BATF finishes their work. A suppressed SBR 300 BO by Novistke (spelled wrong I think). I will start the SBR out with the standard spring and see if it will function with H110. I will report back, just not sure when as it is up to Uncle Sam right now.

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454Puma · « **Reply #24 on:** April 04, 2013, 05:57:55 AM »

Well I got sort of a reply from the AAC rep. They say there 300 blk are made for Surpressed use IE if your carbine isn't surpressed it may or may not cycle subs!

I think thats really stupid cause not everyone wants to spend $200 on the tax stamp! I'm so glad I bought my CMMG 16" carbine now! I have zero problems shooting subs in mine without a surpressor!

Have you tried any factory subs?

bikerbeans · « **Reply #25 on:** April 04, 2013, 11:25:46 AM »

454

I am too cheap and too hard headed to buy factory ammo.

If I was the only one shooting the gun factory ammo would be a possiblity but with my wife and son shooting, Donald Trump couldn't afford to buy factory ammo for them. I have 300 rds loaded for them to shoot in the morning and I bet it is gone as fast as I can stuff it in a magazine.

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454Puma · « **Reply #26 on:** April 04, 2013, 01:29:55 PM »

So have you tried this 5744?

bikerbeans · « **Reply #27 on:** April 06, 2013, 01:39:32 AM »

Quote from: 454Puma on April 04, 2013, 01:29:55 PM

So have you tried this 5744?

No I haven't yet. I also found two pounds of RL7 to work with as well. I am going to save the slower powders until my son gets back from his deployment and gets the paperwork for his can and SBR. It will probably be August before I start working with these two powders. This will give me time to setup powder coating of the Lee boolits as the tumble lube leaves a lot to be desired.

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